ngrep命令用法

  • A+
所属分类:Linux命令

ngrep 是grep(在文本中搜索字符串的工具)的网络版,他力求更多的grep特征,用于搜寻指定的数据包。正由于安装ngrep需用到libpcap库, 所以支持大量的操作系统和网络协议。能识别TCP、UDP和ICMP包,理解bpf的过滤机制。

语法

选项

Allowable primitives are:
dst host host
True if the IP destination field of the packet is host, which may be either an address or a name.

src host host
True if the IP source field of the packet is host.

host host
True if either the IP source or destination of the packet is host. Any of the above host expressions can be prepended with the
keywords, ip, arp, or rarp as in:
ip host host
which is equivalent to:

ether dst ehost
True if the ethernet destination address is ehost. Ehost may be either a name from /etc/ethers or a number (see ethers(3N) for
numeric format).

ether src ehost
True if the ethernet source address is ehost.

ether host ehost
True if either the ethernet source or destination address is ehost.

gateway host
True if the packet used host as a gateway. I.e., the ethernet source or destination address was host but neither the IP source
nor the IP destination was host. Host must be a name and must be found in both /etc/hosts and /etc/ethers. (An equivalent
expression is
ether host ehost and not host host
which can be used with either names or numbers for host / ehost.)

dst net net
True if the IP destination address of the packet has a network number of net. Net may be either a name from /etc/networks or a
network number (see networks(4) for details).

src net net
True if the IP source address of the packet has a network number of net.

net net
True if either the IP source or destination address of the packet has a network number of net.

net net mask mask
True if the IP address matches net with the specific netmask. May be qualified with src or dst.

net net/len
True if the IP address matches net a netmask len bits wide. May be qualified with src or dst.

dst port port
True if the packet is ip/tcp or ip/udp and has a destination port value of port. The port can be a number or a name used in
/etc/services (see tcp(4P) and udp(4P)). If a name is used, both the port number and protocol are checked. If a number or
ambiguous name is used, only the port number is checked (e.g., dst port 513 will print both tcp/login traffic and udp/who traf-
fic, and port domain will print both tcp/domain and udp/domain traffic).
src port port
True if the packet has a source port value of port.

port port
True if either the source or destination port of the packet is port. Any of the above port expressions can be prepended with
the keywords, tcp or udp, as in:
tcp src port port
which matches only tcp packets whose source port is port.

less length
True if the packet has a length less than or equal to length. This is equivalent to:
len <= length.

greater length
True if the packet has a length greater than or equal to length. This is equivalent to:
len >= length.

ip proto protocol
True if the packet is an ip packet (see ip(4P)) of protocol type protocol. Protocol can be a number or one of the names tcp,
udp or icmp. Note that the identifiers tcp and udp are also keywords and must be escaped via backslash (\), which is \\ in the
C-shell.

ip broadcast
True if the packet is an IP broadcast packet. It checks for both the all-zeroes and all-ones broadcast conventions, and looks
up the local subnet mask.

ip multicast
True if the packet is an IP multicast packet.

ip Abbreviation for:
ether proto ip

tcp, udp, icmp
Abbreviations for:
ip proto p
where p is one of the above protocols.

实例

抓本机eth0 与192.168.1.9的通信信息,并且以行来打印出来

抓本机与192.168.1.8的通信端口为80(本机)的信息

抓本机与192.168.1.8和192.168.1.9的通信,并且本地端口为80

抓udp包

ngrep

统计请求头长度

查询一下大于 1K 的请求头

weinxin
微信公众号
扫一扫关注运维生存时间公众号,获取最新技术文章~
默北

发表评论

:?: :razz: :sad: :evil: :!: :smile: :oops: :grin: :eek: :shock: :???: :cool: :lol: :mad: :twisted: :roll: :wink: :idea: :arrow: :neutral: :cry: :mrgreen:

目前评论:1   其中:访客  1   博主  0

    • 匿名 9

      1321阿斯蒂芬